Patch testing in children with hand eczema. A 5-year multicentre study in Spain

Background. Hand eczema is common in children, but affected children are seldom patch tested. Relatively few studies have assessed patch testing in the paediatric population, and none has specifically evaluated its use in hand eczema in children. Objectives. The aim of this study was to determine the prevalence of contact allergy in children with hand eczema, and to identify the most frequent allergens and their relevance. Material and methods. We performed a 5‐year retrospective study of children (aged 0–15 years) with hand eczema tested with the Spanish baseline series at the Dermatology Departments of 11 Spanish hospitals. Results. During the study period, 11 729 patients were patch tested, of whom 480 were children. Hand eczema was present in 111 (23.1%) of the children and in 3437 (30.5%) of the adults. Of the children with hand eczema, 46.8% had at least one positive reaction in the patch tests. Current relevance was found for 78% of the allergens detected. The most common allergens were nickel sulfate, methylchloroisothiazolinone/methylisothiazolinone, and fragrance mix I. Allergic contact dermatitis was the most frequent diagnosis (36%), followed by atopic dermatitis. Conclusions. Allergic contact dermatitis was the most usual diagnosis in our series of children with hand eczema. We recommend patch testing of all children with chronic hand eczema, as is already performed in adults.     

Clinically relevant patch test reactions in children--a United States based study

Allergic contact dermatitis in the pediatric population is more common than previously recognized, with recent prevalence estimates of positive patch test reactions in the range of 14-70% of children patch tested. The aim of this study was to confirm the prevalence of clinically relevant allergic contact dermatitis in children at two referral centers and determine the most common contact allergens. We performed a retrospective case series analysis of 65 symptomatic children (35 girls and 30 boys) aged 1-18 years old who were patch tested over a 5-year period for recalcitrant dermatitis. Positive patch test reactions were noted in 54 of the 65 children (prevalence rate of 83%) to 80 different allergens. Fifty children (77%) had positive reactions which were determined to be of "definite" or "probable" current clinical relevance. We conclude that the diagnosis of allergic contact dermatitis to specific relevant allergens is common in children referred for patch testing and that contact allergy should be considered in all children with recalcitrant dermatitis. With this article, we review the literature and present a US based study regarding the clinical relevance of positive patch test reactions in children.     

Patch testing in children

92 children (45 girls, 47 boys), mean age 9.3 years (3-14.75), were referred to the Contact Dermatitis Investigation Unit, Belvidere Hospital, Glasgow, for patch testing during the period 1979–93 for the investigation of allergic contact dermatitis (ACD). The diagnoses at the time of referral were atopic dermatitis (45). non-atopic with localized dermatitis (26), juvenile plantar dermatosis (15), orofacial granulomatosis (2), vaccination reaction (2) and atypical psoriasis (2). In total, there were 55 positive reactions in 30 children. The commonest allergens were metals (18), fragrances (11) and rubber compounds (6). The patient groups with the highest yield of positive patch tests were those patients with atopic dermatitis who had a good history of a precipitating contact factor (4/5), and non-atopic patients with dermatitis of hands and/or feet (7/14). Our findings suggest that allergic contact dermatitis is more common in children than generally appreciated and that patch testing is a practicable and clinically worthwhile procedure in children.     

Positive patch tests with a dermatophagoides mix relate to an increased responsiveness to standard patch test allergens

The diagnostic meaningfulness of patch tests with house dust mite allergens is still questionable. Our own impression has been that positive results with a dermatophagoides mix may occur preferentially in patients with a generally enhanced responsiveness to contact allergens. To check this, all of our patients allocated to patch testing with the standard series were additionally patch tested with a dermatophagoides mix by the same technique that was used for standard contact allergens. Out of 571 patients tested, 188 showed delayed responses to this mix that were indistinguishable from typical allergic patch test reactions but of no apparent clinical relevance. No relationship was found between positive dermatophagoides patch tests and an atopic disposition of the patients or characteristics of their eczema. However, 64.4% of the patients with a positive dermatophagoides patch test showed a response to at least 1 contact allergen of the standard series, compared to only 56.4% of the patients without a positive dermatophagoides reaction (p < 0.05). The reactivity to the mite mix was not related to the responsiveness towards any particular contact allergens. We suppose that some unidentified factors may contribute to positive reactions to the dermatophagoides mix that may also favour an enhanced general responsiveness to contact allergens.     

Allergy to 3-nitro-p-hydroxyethylaminophenol and 4-amino-3-nitrophenol in a hair dye

Contact allergy to 3‐nitro‐p‐hydroxyethylaminophenol in a hair dye is described for the first time. p‐Phenylenediamine is the most common screening allergen when allergic contact dermatitis is suspected, but sometimes the allergen is not sufficient for diagnosing allergic contact dermatitis to hair dyes. A 50‐year‐old woman developed a severe scalp dermatitis and developed vesicular hand eczema for the first time in her life. Patch testing was performed with the European Standard Series. The patch testing was supplemented with a local series of cosmetic allergens and the hairdresser's series. At the initial patch testing, there was a + reaction to nickel and a +? to PPD at days 3 and 7. Further, she reacted with a +? to her own hair collected at day 3 after the hair dying which elicited the dermatitis reaction. Open exposure to the product, which had initiated the dermatitis, was negative both before and after the allergic reaction to the product. None of the screening chemicals in the hairdresser's series gave a definite positive reaction. Only by patch testing with the individual hair dye product ingredients, the patient's reactions were explained. The patient gave a positive patch test to 4‐amino‐3‐nitrophenol and 3‐nitro‐p‐hydroxyethylaminophenol at days 3–4 reading.     

过敏性皮肤病患者斑贴试验结果分析及临床意义

目的研究过敏性皮肤病患者斑贴试验结果及临床意义.方法对254例湿疹、56例慢性荨麻疹、28例特应性皮炎患者进行斑贴试验检测.结果三组患者中阳性率较高的致敏原有四种物质相同,分别为硫酸镍、重铬酸甲、卡巴混合物、芳香混合物;特应性皮炎组阳性率(64.29%)明显低于湿疹组(79.92%),慢性荨麻疹(76.79%)与湿疹二组阳性率之间差异无显著性.结论过敏性皮肤病患者阳性率较高的致敏原具有相同性;硫酸镍、重铬酸甲、卡巴混合物、芳香混合物具有较高的致敏性;斑贴试验主要用于检测外源性变应原,特应性皮炎的病因可能以内源性为主;接触性过敏原可以引起接触性荨麻疹;斑贴试验阳性致敏原常是引起面部湿疹、手湿疹的致病因素.     

The detection of clinically relevant contact allergens with a standard screening tray of 28 allergens

Background. A standard method for diagnosing allergic contact dermatitis in the United States is the Thin‐layer Rapid Use Epicutaneous (TRUE) test (TRUE Test?), which consists of three panels containing 20 individual allergens and eight allergen mixes. Previous studies had raised concern regarding the adequacy of the initial two‐panel TRUE Test? system (16 individual allergens and seven allergen mixes) in fully assessing patients with possible allergic contact dermatitis. Objectives. We sought to investigate the effectiveness of the current three‐panel TRUE Test? as the sole diagnostic tool for detecting allergic contact dermatitis. Patients/materials/methods. This study was a retrospective analysis of 2088 patients who underwent patch testing between 1995 and 2010. Study groups were analysed to determine whether positive reactions were to allergens and/or mixes present in the TRUE Test? panels. Results. Of the 2088 patch‐tested patients, 1385 had at least one positive reaction. Among these 1385 patients, 27.6% were fully evaluated by use of only the TRUE Test? series, 49.9% were partially evaluated, and 22.5% did not have any of their allergens detected. On assessment for clinical relevance, similar percentages were observed. Conclusion. In our study, the current TRUE Test? series of 28 allergens would have completely identified allergens in only 27.6% of patients. Broadening the standard panel to include common allergens causing >50% of allergic contact dermatitis cases in a given geographical location and aim testing allergens on the basis of the patient's history will increase the test's sensitivity.     

Environmental contact factors in eczema and the results of patch testing Chinese patients with a modified European standard series of allergens

Environmental contact factors in eczema were investigated in China by clinical questionnaire and patch testing patients with a modified European standard series of allergens. 217 consecutive eczema patients were studied. Contact dermatitis (CD) was clinically diagnosed in 30% of the patients. Among the patients patch tested, 46 patients had clinically diagnosed allergic CD (ACD), 20 patients clinically had non-ACD (NACD) (including 16 cases of irritant contact dermatitis, 1 case of phototoxic contact reaction and 3 cases of asteatotic eczema) and 115 patients had clinically suspected ACD. 45 patients (98%) in the ACD group went on to have relevant patch test results. The most common ACD was from metals, fragrance materials, cosmetics and rubber materials. The most common contact allergens identified were nickel, fragrance mix, para-phenylenediamine (PPD), carba mix and thimerosal. No adverse reactions were observed to patch testing, except for pruritus in patch-test-positive patients. The positive rate of patch testing in ACD was much higher than that in NACD (98% versus 15%, P < 0.05, chi(2)-test). 60 (28%) patients had facial dermatitis (FD). Among these, 20 (33%) were confirmed as having ACD. 48 (22%) patients had hand dermatitis (HD). Among these, 7 (15%) were confirmed as having ACD. Fewer patients were confirmed as having ACD in the HD group than in the FD (15% versus 33%, P < 0.05, chi(2)-test). Although the difference was not significant, the total positivity rate in the HD group (55%) was lower than in the other groups. 65 (30%) patients had unclassified endogenous eczema (UEE). The total positive rate of patch testing in the UEE group (56%) was no different from that in the FD or HD groups. However, the relevance of positive patch tests was hard to determine in UEE. These results indicate that CD is common in eczema; relatively more patients with FD have ACD, while other factors, such as irritation, may play more of a role in HD. The total positive rate of patch testing in the UEE group was no different from that in the FD or HD groups, suggesting that patch testing should be stressed in UEE and the relevance of positive patch test results in UEE should be studied further. It is effective and safe to patch eczema patients with a modified European standard series of allergens in China.     

Non-fragrance allergens in specific cosmetic products

Objectives. Reports about the nature of the ingredients responsible for allergic contact dermatitis caused by specific cosmetic products are scarce. Methods. Between January 2000 and December 2010, the specific cosmetic products having caused allergic contact dermatitis, as well as the individual allergenic cosmetic ingredients present in them, were recorded by use of a standardized form. Results. Among 11 different categories of cosmetic product, skin care products, followed by hair care and body‐cleansing products, were most often involved. The presence of the allergenic ingredient(s) in a specific cosmetic product was confirmed according to the ingredient label in 959 of 1448 records. Six hundred and twenty‐one of 959 concerned non‐fragrance components, preservatives being responsible for 58% of them. Reactions to formaldehyde and formaldehyde‐releasers were most often correlated with body‐cleansing products, particularly 2‐bromo‐2‐nitropropane‐1,3‐diol and skin care products. They were followed by the methylchloroisothiazolinone/methylisothiazolinone mixture, most frequently found as allergens in hair care and intimate hygiene products, and facial cleansers (in the last category together with diazolidinyl urea). Octocrylene was by far the most frequent (photo)allergen in sun care products. Conclusions. This study provides information on the presence and frequency of allergens in specific causal cosmetic products.     

Patch testing in children – recommendations of the German Contact Dermatitis Research Group (DKG)

Allergic contact dermatitis occurs frequently in children. Patch testing is needed to identify the responsible allergens and should be performed in children. We recommend a panel of 12 contact allergens as a standard series in children from 6–12 years. Four additional contact allergens should be tested in case of a positive history or suggestive clinical picture. For patch testing in children, the allergens should be applied for 24 hours and the readings should be performed at 48 and 72 hours. Standardized patch testing makes it possible to systematically investigate allergic contact dermatitis and identify relevant allergens in children.     

Active participation of eosinophils in patch test reactions to inhalant allergens in patients with atopic dermatitis

Intracutaneous testing and patch tests with house dust mite and grass pollen allergens were performed in patients with atopic dermatitis. Only patients with an immediate type skin reaction to house dust mite or grass pollen allergens showed a positive patch test reaction to these allergens 24-48 h after testing. Occasionally positive patch test reactions at 20 min, 2 h and 6 h were also observed. Patch test reactions were not found in normal controls or atopic patients without atopic dermatitis. Analysis of the cellular infiltrate demonstrated an influx of eosinophils into the dermis, starting from 2-6 h after patch testing. Immunostaining with antibodies against granular constituents of the eosinophils revealed that the infiltrating eosinophils were in an activated state and had lost part of their granular contents. At 24 h eosinophils also appeared in the epidermis. Electron microscopy showed that in the epidermis, some eosinophils were in close contact with Langerhans cells, suggesting a cell-cell interaction. Taken together, these results strongly suggest an active role for eosinophils in patch test reactions to inhalant allergens in atopic dermatitis patients.     

Recalcitrant atopic dermatitis due to allergy to Compositae

Atopic dermatitis is often complicated by allergic contact dermatitis, although patch testing may reveal positive reactions of uncertain relevance. We report a case of a 35-year-old woman with recalcitrant atopic dermatitis, with a positive patch-test reaction to Compositae mix (CM). Initially, sensitization appeared to be of past relevance only, due to use of calendula. However, it turned out that she followed a self-devised diet consisting largely of food products of the Compositae family. On excluding these food products her skin condition improved quickly. This case report underscores the difficulty in determining the relevance of positive patch tests, and shows that thorough analysis of positive patch tests, by both patient and physician, may reveal unexpected or less common sources of contact allergens.     

Patch testing: Uses,systems, risks/benefits,and its role in managing the patient with contact dermatitis

Patch testing is the gold standard diagnostic tool for cell-mediated type IV hypersensitivity reactions like allergic contact dermatitis. Sensitized individuals have primed antigen-specific T lymphocytes that cause a reaction when antigens are applied to the skin owing to prior sensitization. Patch testing can be used in the adult and pediatric populations, but it is contraindicated in patients with a known history of severe allergic reactions to suspected allergens, generalized active dermatitis, or extensive eczema. Patch test systems can be a comprehensive panel (70-80 allergens), but they can also be targeted and limited to a more common allergen series (35 allergens). The decision for allergen selection should be based on an accurate patient history, physical examination, and availability of allergens. Measurement and interpretation of the test results requires training and experience, as well as consideration of relevance and clinical history. Patch testing is generally considered safe with just a few known complications: excited skin syndrome, active sensitization, and rarely anaphylaxis or other cutaneous complications. Appropriately pretesting patient education can help to mitigate some of these complications. Based on patch testing results, patients should be educated regarding proper allergen avoidance measures to resolve symptoms of allergic contact dermatitis.     

Allergic contact dermatitis in 136 children patch tested between 2000 and 2006

Background  Allergic contact dermatitis is often under-recognized in the pediatric population but it may affect greater than 20% of this age group.
Methods  We conducted a retrospective review of the Mayo Rochester, Jacksonville and Arizona patch test database of all children 18 or younger over a 7-year period (January 1, 2000–December 31, 2006).
Results  One-hundred thirty-six children were patch tested from age 3 to 18. Females constituted 66% of those tested and males 34%. Eighty percent of the children were equally distributed between age groups 11–15 and 16–18, with the remainder being 10 years or younger. Sixty-one percent of the children tested positive to at least one allergen. Fifty-three percent of these reactions were deemed to be of current relevance, 31% questionable relevance, 5% past relevance, and 10% not relevant. Males younger than 10 were most likely to have a positive patch test. However, the percent of positive tests in males decreased with increasing age. Females younger than age 10 were less likely to have a positive test than older females. The most common allergens were nickel, cobalt, gold, and thimerosal.
Conclusion  In children suspected to have allergic contact dermatitis, 61% were confirmed to have a positive reaction to at least one allergen. The utility of patch testing children whose clinical presentation is suggestive for allergic contact dermatitis is high.     

Contact hypersensitivity and allergic contact dermatitis among school children and teenagers with eczema

Background:  Patch testing is an essential procedure in the investigation of eczema in children.
Objectives:  To analyse the frequency of contact hypersensitivity and allergic contact dermatitis among Polish children with eczema.
Patients/methods:  During an allergy screening programme involving 9320 children aged 7 and 16 years, 12.6% reported symptoms of chronic/recurrent eczema. From this group, a representative sample of 229 eczema children underwent patch testing: 96 children aged 7 years and 133 teenagers aged 16 years. Patch testing was with 10 allergens: methylchloroisothiazolinone/methylisothiazolinone (MCI/MI), nickel sulfate, mercury ammonium chloride, thimerosal, cobalt chloride, potassium dichromate, lanolin, fragrance mix I, Myroxylon pereirae (balsam of Peru), and colophonium.
Results:  49.4% tested children were found patch test (PT) positive. 43.8% of 7 year olds with eczema were PT positive, with sensitization to nickel sulfate (30.2%), thimerosal (10.4%), cobalt chloride (8.3%), fragrance mix I (7.3%), MCI/MI (6.3%), potassium dichromate (6.3%), M.   pereirae (3.1%), mercury ammonium chloride (2.3%), and colophonium (1.0%). 52.6% teenagers were PT positive, with sensitization to nickel sulfate (23.3%), thimerosal (27.8%), cobalt chloride (10.5%), potassium dichromate (6.0%), mercury ammonium chloride (2.3%), M. pereirae (1.5%), and MCI/MI (0.8%). The final diagnosis of allergic contact dermatitis was confirmed in 36% of 7 year olds and 26% of 16 year olds.
Conclusions:  Every second child with eczema is PT positive, whereas every third child is finally diagnosed with allergic contact dermatitis.     

Patch test reaction on Ethiopian subjects with eczema

Background  Allergic contact dermatitis is a common condition with an incidence of 1–10% in the general population. An increasing number of allergens in the environment are responsible for the condition. These allergens can be identified using patch testing. Many countries have a standard series of common allergens used for patch testing. There is no standard series of allergens in Ethiopia, and our objective was to obtain baseline data for common allergens for future standardization.
Methods  One hundred and eighty-one subjects with eczema were patch tested using 17 selected allergens from Chemotechnique Diagnostics AB employing a standard procedure.
Results  Positive patch test reactions were detected in more than 60% of subjects, the most common allergen being nickel, followed by fragrance mix and butylphenolformaldehyde. A higher incidence of positive reactions was seen in females.
Conclusions  A high incidence of positive patch test reactions was identified in the study population, and the introduction of patch testing in Ethiopia is essential for the management of allergic contact dermatitis.     

Patch testing and contact allergens in Ethiopia – results of 514 contact dermatitis patients using the European baseline series

Background: Patch testing is essential to diagnose allergic contact dermatitis. Dermatologists in many countries use a baseline (standard) series covering the major allergens responsible for allergic contact dermatitis in their population, with the addition of relevant allergens for the individual patient. However, a baseline series has not yet been developed for Ethiopia. Our objective in this study is to identify common contact allergens to form the basis of a future baseline series in Ethiopia. Methodology: We patch tested 514 subjects with dermatitis according to the recommended procedure using the European baseline series for 1 year. Results: 52.7% of the tested subjects showed positive reaction for at least one allergen tested. The top five contact allergens identified were nickel sulfate, fragrance mix I, cobalt chloride, p‐tert‐butylphenolformaldehyde (PTBP) resin and potassium dichromate. Positive reactions to nickel and PTBP were commoner in females. PTBP positivity was strongly associated with foot eczema. Positive test reactions were commoner in cement workers, notably to potassium dichromate, which was also a commoner allergen in patients presenting with hand dermatitis. There were no reactions to several allergens, including neomycin, benzocaine, budesonide, primin and quaternium‐15. Conclusion: Comparable patch test results with other countries have been shown and the European baseline series can be used as a baseline series in Ethiopia with some modification.     

Flare factors and atopic dermatitis: the role of allergy

Atopic dermatitis is a genetically determined eczematous skin disease strongly influenced by environmental conditions called flare factors. Allergic reactions are one such flare factor. These reactions include contact urticaria, allergic contact dermatitis, and late phase reactions. Contact urticaria could induce eczema by eliciting scratching. A late phase reaction may be involved in eczema produced by prolonged epicutaneous applications of antigens in individuals with immediate sensitivity to these antigens. Mechanisms of allergic contact dermatitis might also elicit dermatitis. Environmental allergens may include mold, dust, mite, pollens, foods, danders and bacteria.     

The importance of checking for delayed reactions in pediatric patch testing

Abstract: Patch testing is often performed with the final reading being completed at 72 hours. Studies in adults have shown that performing an additional reading several days later increases the yield of relevant positive reactions. We report a study of this matter in children. We conducted a prospective patch test study of 38 affected children aged 6 to 17 (mean 11.6 years), with presumed allergic contact dermatitis between April and July 2009. The patients were required to return at 48 hours for patch test removal and assessment of early reactions, at 72 to 96 hours (3–4 days) for evaluation of delayed reactions, and again at 168 to 216 hours (7–9 days) for a final late delayed reading. We tallied the number of patients with “equivocal” (+/?), +, ++, and +++ reactions and noted these as potential positive reactions by reading date. Twenty‐five of the 38 children (66%) had a positive reaction at 48 hours; 32 children (84%) had a positive reaction at 72 hours (day 3); 19 children (50%) had a positive reaction at 168 to 216 hours (day 7–9). Of those 19, 16 (42%) had persistent reactions, while 5 children (13%) had new late delayed reactions. Among the new late delayed reactions, there were six allergens identified, four of which were considered of probable clinical relevance. When patch testing with Thin Layer Rapid‐Use Epicutaneous test panels, a delayed reading beyond 72 hours may be needed to identify the offending agent(s) responsible for allergic contact dermatitis in some children. Additional studies are needed to assess optimal readings schedules.     

Patch testing in Israeli children with suspected allergic contact dermatitis: A retrospective study and literature review

Background/objectives

Childhood allergic contact dermatitis is recognized as a significant clinical problem. The objective was to evaluate the rate of positive patch tests in Israeli children with clinically suspected allergic contact dermatitis, identify possible sex and age differences, compare results with those in Israeli adults, and review pediatric studies in the literature.

Methods

The study sample included 343 children and adolescents (197 female, 146 male; 1‐18 years of age, mean age 11.8 years) with clinically suspected allergic contact dermatitis who underwent patch testing with a standard pediatric series of 23 allergens at a tertiary medical center from 1999 to 2012. Data on clinical characteristics and test results were collected retrospectively from the medical files.

Results

Ninety‐eight subjects (28.6%) (75 girls [38.1%], 23 boys [15.8%]) had at least one positive reaction. The most frequent reactions were to nickel sulfate, followed by potassium dichromate and cobalt chloride. Nickel sulfate sensitivity was more common in girls, especially those younger than 3 years and older than 12 years. The prevalence of contact sensitization was similar in subjects with and without atopic dermatitis (50% and 51%, respectively).

Conclusion

Nickel is the most common allergen in Israeli children, especially girls. Patch testing should be performed in children with clinically suspected allergic contact dermatitis regardless of atopic background.